This invention relates to a multi-share plough and particularly, though not exclusively, to a semi-mountable plough of the reversible type, comprising an elongate plough frame carrying a plurality of plough bodies and being supported on wheel means, said elongate plough frame comprising a front plough frame section and a rear plough frame section, with the rear plough frame section being articulated directly to said front plough frame section or indirectly via an intermediate frame section.
In semi-mounted ploughs, the plough frame carries a large number of plough bodies, and therefore the plough frame has to be divided in order to constitute two mutually articulated frame sections, namely a front plough frame section and a rear plough frame section, and optionally with an intermediate frame section between the front and rear plough frame sections.
The purpose of such an articulated plough frame is to allow the plough to follow in a sufficient degree unevennesses and roughness of the ground.
Moreover, long semi-mounted ploughs have a support frame of such a longitudinal extent that the rear end portion possesses a tendency of being deflected resilently.
When the ploughs become very long, the rearmost plough bodies will hang somewhat lower than the intermediate plough bodies. Therefore, this makes it difficult to control the rear portion.
This results in that the rearmost plough bodies - when the plough is placed into the soil at the beginning of each furrow - start to plough simultaneously with the foremost plough bodies. This results in the beginning of each furrow, as seen in a top plan view, after ploughing, showing a triangular area that has become ploughed and a triangular area that has not become ploughed.
With a twelve-share plough, a considerable area will receive such an uneven ploughing.
Normally, this area is ploughed laterally of the furrows in a final ploughing operation. When doing so, the soil becomes partly reversed back again within said triangular areas which already have been ploughed such that the soil which should have been the lowermost, comes uppermost again.
The result of all this is poor and uneven growth within said areas.
Attempts have been made to control the rear plough frame section through locking the link or pivot constituting the articulation between the front and rear plough frame sections or between the latter and an intermediate frame section, respectively, during the lifting and reversal of a semi-mounted reversible plough. Said link or pivot is released whenever the plough once more has taken the ploughing position.
However, such an arrangement does not represent a satisfactory solution.